I think you touched the center point: cyberExperts.
Internet has given us an incredible tool but became also the very best land for "self-promotional-knowledge-and-pride". Everyone has something to say, to write, to show. Everyone needs to be an "expert" to some extend to feel being someone. This is a WW social phenomenon. It doesn't matter if the datas are serious, it just has to look like.
I mean, there are people in youtube that make movies about what will happen to the world the 21th december 2012! And they are serious about it... like if it they had secret information. It probably makes them feel that they belong to a sort of knowledgable circle. Then videos on evil illuminati and free massons leading the world with super trustable datas of course etc...we are inundated by those "experts".
Photography, being a much more democratized medium than cinema wich requires heavy and expensive structures, so kept free of "cyberexperts", is a diamond mine indeed. Because it has all the ingredients for those cyberExperts to express themselves: it's technical but it's not rocket engineering, it has brands and systems wich every "expert" can identify himself with and compeat with the others etc...
So any average "technician" that would have no voice in real science can elaborate theories from things like DXO etc...and it works! more exactly it looks that it works. Internet is absolutly overcrowded by "knowledgable" people mostly in mass product area, like photography.
Strangely, none of those experts are actually engineers currently working for Dalsa or Canon but consummers like you and me. And very few of those "experts" are actually working as professional photographers, or print bigger than 30cm... So inevitably, the information sprayed it's mostly empty, but they will do all they can to make you feel that they know, matter of cyber reputation they put their names on... having the last word is convenient: "I know and you're wrong because this that and the other". They are generally jalous of MFD owners (because hey, they might understand something that they don't or can't access to) that's why they tend to bark very loud, like the very little nervous dog barks always loud when a big german pastor is crossing it's way...
You have some good points there, Fred, and I imagine that, for anyone who is not particularly rational and who might have some difficulty in being objective and unbiased, this state of affairs you describe could be a real problem. Whom to trust?
I imagine such people will simply 'follow the leader' and buy the same equipment that someone whom they admire uses. Problem solved.
Others, such as myself, get a sense of what equipment they need through the feed-back process of taking many images in a variety of circumstances and seeing clearly what works (technically) and what's lacking, whether it be too little detail for a large print, too noisy because of poor high-ISO performance, or too blurred due to a too-slow shutter speed which is related to ISO performance.
For my own purposes, I value good performance at high ISO, as well as good performance at base ISO, because I tend to be a peripatetic photographer rather than a studio worker.
For example, when I got up this morning, on the way from the bedroom to the bathroom to have a pee I noticed the following scene through the laundry glass door.
I grabbed my Canon 50D and quickly attached the 100-400 zoom, and took a series of shots through the glass door, setting the camera at ISO 800. The shutter speed was a bit slow, so I re-set the ISO to 1600 which is the highest ISO that provides reasonable quality on this small-format camera.
Knowing the technical qualities that I desire in a camera (and lenses), I can then search the internet for any tests and comparisons that are available, to help me decide upon the best equipment for my purposes.
This is where sites such as DXOmark, Imaging Resource and dpreview are very useful.
Opinions are cheap. Anyone can have an opinion, but not everyone can back up his opinion with comparison images, or comparison data in the form of graphs.
I find it quite absurd that many owners of DBs claim that DXOmark results are a joke, yet such people never provide any comparison images demonstrating that the DXO data is either false or misleading. Can you believe such people? I don't.
So my advice to you, Fred, is to tackle this confusing mass of opinions on the internet with a very simple procedure. Ask for the evidence. In photography, seeing is believing.